As a memory device of electronic equipment such as a cell phone and a personal computer, a semiconductor memory device using a memory element such as a NAND-type flash memory has been often used these days. As the semiconductor memory device for use in the electronic equipment, a memory card (semiconductor memory card) can be taken as an example.
In the semiconductor memory device, semiconductor chips such as semiconductor memory chips and controller chips are mounted on a wiring substrate with external terminals formed thereon. Electrodes on the semiconductor chip are electrically connected to connection pads on a wiring substrate through wire bonding and further sealed by a resin to cover the whole semiconductor chips.
With a widespread use of this semiconductor memory device, cost reduction in manufacturing the semiconductor memory device is challenged. For example, a method for reducing the cost for manufacturing a semiconductor memory device is disclosed, in which an organic substrate formed by a comparatively expensive material is used for the wiring substrate, in an L-shape in a top view, in a way of restraining the use amount of the organic substrate.
However, an installation area of the semiconductor memory chips occupies a comparatively large area in the semiconductor memory device and formed of an organic substrate. Therefore, the cost reduction effect is restricted.